Alex Keller has worked as The Wiggles' regular sound engineer for nearly all of their live concert tours and studio albums since 1998.
Keller also works as a production crew member on the band's various videos and television shows and as a musician, songwriter, and occasional music producer on the band's albums in addition to engineering them. As a musician, he primarily plays the bass guitar, cello, and steel drum among various other instruments, and has also performed live with the group on rare occasions, most notably in the various reunions of the original band lineup.